Printing-telegraph



C. L. AND H. L. KRUM.

PRINTING TELEGRAPH.

APPLICATION FILED MAR. 7, 1914. RENEWED 05c. 22.1919.

i Q m mg 0 0 T M MML CN' 1m (C v W E Z 3H 24L MW mm E w as m m P C. L.AND H. L. KRUM.

PRINTING TELEGRAPH.

1 WI} AWN C. L. AND H. L. KRUM.

PRINTING TELEGRAPH.

APPLICATION FILED MAR. 7, I914. RENEWED DEC. 22,1919.

1 ,360,23 1 Patented Nov. 23, 1920.

6 SHEETS-SHEET 3.

C. L. AND H. L. KRUM.

PRINTING TELEGRAPH.

APPLICATION FILED MAR. 7. 1914. RENEWED DEC. 22.1919.

[l /(5)365. Q 5; 8W JW .c. L. AND H. L. KRUMf PRINTING TELEGRAPH.

APPLICATION FILED MAR. 7, I914. RENEWED DEC. 22, I919.

Patented Nov. 23, 1920.

6 SHEETS-SHEET 5.

H I Hl I l r l l l l l l H l l l l l l I ll C. L. AND H. L. KRUM.

PRINTING TELEGRAPH. APPLICATION FILED MAR. 7, 1914. RENEWED DEC. 22.1919.

Patented Nov. 23, 1920.

crating magnets.

umrso STATES PATENT; option] CHARLES L. KRUM AND HOWARD L. KRUM, orciarcaco, ILLINOIS, Assreivons 'ro monxnum COMPANY, or onrcneo, nmmorsnCORPORATION.

PRINTING-TELEGRAPH.

Specification of Iietters Patent. Patented No 23 1920 Application filedMarch 7, 1914, Serial No. 823,100. Renewed December 22, 1019. Serial No.346,770.

To all whom it may concern:

Be it known that we, CHARLES L. KRUM and HOWARD L. KRUM, citizens of theUnited States, and residentsof Chicago, county of Cook, and State ofIllinois, have invented certain new and useful Improvements inPrinting-Telegraphs, of which the following is a full, clear, and exactdescription.

The invention relates to printing t e1egraphs of that type in which eachstation is provided-with rotatable transmitting and receiving switchmechanism, and in which suitable means is provided for maintaining thereceiving switch mechanism at one station in synchronism with thetransmitting switch mechanism at a distant station. The presentinvention seeks to provide an improved printing telegraph of, this sortwhich is simple in its construction and arrangement and which iseflFicientv and reliable in operation. The invention also seeks toprovide improved station instruments having means for driving therotating transmitting and receiving switches or sunflowers and means formaintaining the same in synchronism at two stations which are incommunication. A further object of the inven tion is to provide improvedmeans for con trolling, through the medium of a tape, the impulses\imparted to the line by the transmitting switch and to provide improvedmeans controlled by the receiving switch in response to impulsesreceived from a distant station for actuating selecting and op- Withthese and other objects in view, as will presently appear, the inventionconsists in the features of improvement hereinafterset forth,illustrated in the preferred form. and arrangement in the accompanyingdrawings and more particularly pointed out in the appended claims.

In the drawings, Figure 1 is a plan view of one of the stationinstruments. Fig. 2 is a View in side elevation with the transmittingand receiving disks shown in section.

Figs. 3, 4, 5 and 6 are detail sections on lines v is a plan view of amodification of the station instrument. Fig. 10 is a detail section onthe line 10-10 of Fig. 9. Fig. 11 is a dia- I gram of the arrangement ofthe circuits at two connected stations' Fig. 12 is a diagram of the mainline circuits employed in connection with the instrument shown in Fig.9. 2

The improved station instrument is mounted upon a base plate 10. Intheform shown in Figs. 1 and 2, the transmitting and receiving switches aremounted upon a common horizontal shaft 11 that extends centrally throughannular or ring-like portions 12 of a pair of brackets 13 that extendupwardly from the base plate 10. At its outer end the shaft 11 isjournaled in a U-shaped member 14 which is fixed to and extends acrossthe annular portion or ring 12 of the outer bracket 13. At its oppositeend, the

shaft 11 is journaled in an upright 15 that is mounted on the base plate10. The contacts of the transmitter switch are mounted upon a ring orannular disk A which is fixed to the ring portion 12 of the innerbracket 13 and extends about the shaft 11. The con tacts of thereceiving switch are mounted upon an annular-disk. or ring B ofinsulating material that is carried upon the ring portion of the outerbracket. The receiver disk B is preferably so mounted that it may berotatably adjusted to a limited extent. For this purpose, it is held inplace by a series of clips 16 which are fixed to the ring portion 12 ofthe outer bracket and which overlap and frictionally engage the reducedor rabbeted edge portion 17 of the disk. By means of a radiallyprojecting handle 18 fixed to the receiving disk B, the latter may beadjusted in circumferential direction to a limited extent. A scale (seeFig. 1) marked from the upper edge of the adjacent fixed ring 12 assistsin effecting the proper adj ustment of the receiver disk. H

Boththe transmitter and receiver disks A and B are provided with acircular series of contacts. Each has a series of correspond- Figs. 11and 12) which are used in transmitting and receiving the differentcombinations or permutations which represent the different characters.The transmitter disk is also provided with two contacts 6 and 7 whichimpart the correcting and restoring impulses to the line. In thecorresponding position, the receiver disk is provided with one longcontact 6'. The disks are also preferably provided with an additionalcontact 8 for imparting and receiving warning signals. The contacts, asshown in Fig. 2, are recessed into the faces'of the disks, being held inplace by bolts19 extending through the disks. Nuts 20 on the boltssecure clips 21 to the outer faces of the disks and by which the properconductors are connected to the several contacts. The transmitter anextended portion 23' which carries a pad 24 of felt. A small quantityofoil is placed 1 on these pads and as they sweep over the contacts,they serveto keep them free from dust. Current is transmitted to andfrom the switcharms a and b by insulated brushes 25 that are carriedupon brush-holders 26, (see Fig. 6). These brush-holders are pivotallymounted 'upon an anglebracket 27 fixed to the base plate 10, and springs28 interposed between the brush-holders and clips 29 on the bracketserve to yieldingly press the brushes into engagement with the hubportions or commutators 22 of the switch arms. The conductors leading tothe brushes are connected to insulated clips 30 which are connected tothe brushes by springs 31 and clips 32.

The operating shaftll of the station instrument is continuously driven,when in operation, by, a suitable motor. In the construction shown, asmall electric motor C is mounted upon the base plate 10 and its shaftis provided with a fly-wheel 33 and a small pinion 34. The motor is alsoprovided with a suitable governor (not shown) so that its shaft isrotated at the desired uniform rate of speed. The pinion 34 on the motorshaft meshes with a gear 35 in the main shaft 11. 'hen instruments suchas shown in Figs. 1 and 2 are employed at two communicating stations,one station is provided with a corrected instrument and the other with anoncorrected instrument. In the non-corrected instrument, the gear 35 isfixed to the shaft 11, but in the corrected instrument, it is looselymounted on the shaft and is connected thereto through means by which theshaft 11 can be retarded to thereby maintain the instruments at the twostations in synchronism. I

For this purposef the gear 35 is fixed to one end of a sleeve 36 whichis loosely mounted on the shaft-and extends through the bearing on theupright 15. At its opposite end, the sleeve is provided with a gear 37which meshes with a pinion 38 on the stud 39 (see Figs. 3 and 4). Thisstud is eccen- 6 5 trically fixed to a cross arm 40 that is fixed to theshaft 11. A short shaft 41 journaled in the end of the arm 40 carries atone end a star wheel 42 and, at its opposite end, a pinion 43 whichmeshes with the pinion'- 38. A retaining roller 44 engages the teeth ofthe star wheel 42. This roller is mounted upon an arm 45 which ispivoted on the arm 40 and which is connected thereto by a spring 45. Theend 40' of the arm 40 is weighted to counterbalance the gearing on theopposite end of the arm. The spring 45' holds the roller in engagementwith the star wheel and prevents the relative rotation of the train ofgears 37, 38 and 42, so that normally the shaft 11 rotates with thedrive gear 35. But, by projecting a pin 46 into the path of movement ofthe star wheel, it and its shaft 41 may be caused to rotate through thespace of one tooth and thereby, through the medium of the pinions 42 and39, retard the movement of the arm 40 and shaft 11 relatively to thedrive gear 35.

The pin 46 (see Fig. 2) is mounted to slide longitudinally in a suitableguide in the upper end of a'bracket 47 that is fixed to the base plate10. A double spool magnet D mounted upon the lower portion of theupright 47 is provided with an armature (i on a pivoted lever (13'. Aheaded stop pin 48 fixed to the upright extends through the armaturelever d and a spring 49 coiled about the stop pin extends between theupright and the armature lever and normally holds the latter against theouter headed end of the stop pin. The upper forked end of the armaturelever is arranged between collars 50 on the pin 46. Normally, the spring49 holds the pin 46 out of the path of movement of the star wheel 42.But, when the correcting magnet D is energized, the pin 46 is shifted sothat it engages the starwheel and retards the movement of the shaft 11and of the transmitter and receiver switch arms a and b actuatedthereby.

As hereinafter explained, the circuit of the correcting magnet iscontrolled by the combined operation of the line relay and of a switchcontrolled by a cam 0 upon the main shaft 11 of the instrument. In theconstruction shown, this cam is conveniently mounted on the shaftbetween the switch arm hubs 22 and is insulated therefrom and from theshaft. As shown, the cam is engaged by the upper, offset end of a switcharm E. .T his switch arm is mounted upon a brush-holder 26 which issimilar in all respects to the holders for the brushes 25. previouslydescribed, and which is pivotally mounted therewith upon the anglebracket 27. The switch E cooperates with an adj ustable contact screw Ewhich is carried upon an upturned lug 51 of a cross piece 52 thatextends between the uprights 13. Through the greater portion of therevolution of the shaft 11, the cam (3 holds the brush E out of p'ulsesimparted to the line are determined by a series of. switches which inturn are controlled by a perforated tape. The present invention providesimproved means for driving the tape from the shaft 11. As

shown in Figs. 1, 2, 3 and 5, an upright plate 53 is fixed to one edgeof the base plate 10 by angle brackets 54. A ledge 55 fixed to the outerface of the plate 53 forms a guide for the tape F. At its inner edge,the ledge is provided with a guiding shoulder 56 and at its outer edgewith guide pins 57. In operation, the tape F is passed over the surfaceof the ledge between the shoulder 56 and the guide pins and beneath ashort plate 58 that is fixed to the inner raised portion of the ledge55.

A stud 59 is fixed to the upright plate 53 and projects outwardly overthe plate 58. A series of washers 60 are eccentrically mounted on thestud 59 and a set of five switch arms f extend through the washers onone side of the stud 59 and are fixed in position by set screws 61. Theupper ends of the switch arms are guided by a comb bar 62 that projectslaterally from the upright plate 53 and are arranged to engage a set offive insulated contacts 63. The contacts 63 are adjustably mounted in asuitable support 64 that projects laterally from the plate 53. Rods 65also project laterally from the plate 53 and a series of sprin s 66extend between the rods 65 and the switch arms and tend to hold thelatter in engagement with the contacts 63.

The lower pointed ends of the switches f extend through openings in theplate 58 and into the guideway for the tape between the plate 58 and theledge 55. The tape F is provided with transverse rows of perforationswhich are varied, so that each of such rows represents a differentcharacter or signal. The switch contact 63 is so adjusted that, when notape is present in the guideway, the switches will engage the contactand, when the tape is in position, the switches will be held out ofengagement with the contacts unless the lower end of one or more of theswitches drops into a perforation in the tape. When the lower end of anyswitch drops into a perforation, it is quickly shifted by its spring 66into engagement with the corresponding contact 63 and when theimperforate portions of the tape pass its contact. T ese switches thusserve to select the impulses which are imparted to the line by therotating transmitter switch a. The row of switches is arranged at rightangles to the path of movement of the tape F, but the transverse rows ofperforations F are arranged at a slight angle to the row of switches, sothat the tape maybe continuously driven in definite timed relation tothe operation of the transmitter switch arm.

The tape F is advanced by a pin toothed wheel 67 arranged beneath theguide ledge 55 and the teeth of which project upwardly through slots inthe ledge and in the plate 58, and into engagement with the longitudinalrow of perforations F in the tape. Feed wheel 67 is mounted upon theouter end of a shaft 68. This shaft extends through a vertical slot '69in the upright plate 53 and is journaled in the depending end portionsof a U-shaped bracket or support 70. The inner forked end of the support70 is pivotally mounted upon the main drive shaft 11 and a worm 71 fixedto the shaft 11 meshes with a worm wheel 72 on the inner end of the feedshaft 68. The support 70 and parts carried thereby are normally upheldby a s ring 73 fixed thereto and to a stud 74 on t e upright plate 53.An adjustable stop screw 75 extends through a lug 76 on the face of theplate 53, engages the support 70 and holds the parts carried thereby innormal position. The outer end of the shaft 68 is knurled and forms afinger-piece by which the shaft may be depressed against the tension ofthe spring 73 to thereby depress the teeth of the pin wheel 67 below theupper face of the ledge 55,

whereon the tape is guided, to thereby permit the ready removal orinsertion of the tape.

The outer end of the support 70 is pro-- vided with a pair of lugs 77(see Fig. 5) which engage one arm 78 of a bell crank which is pivoted onthe inner face of the upright plate 53. The other arm 79 of the bellcrank is connected by a link 80 to a in 81, as most clearly shown inFig. 7. is pin extends through a horizontal slot 82 in the plate 53 andengages the selecting switches 7 above the stud 59 whereon" the switchesare pivoted. hen the outer ends of shaft 68 and support 70 aredepressed, the pin 81 is moved against the switches by the connectionsdescribed, so that their lower ends are lifted out of the path ofmovement of the tape. In this way, both the teeth of the feed wheel 67and the selecting switches may be shifted to permit the ready insertionand removal of the tape. It should be noted that the arrangement is suchthat the feed wheel 61 and selecting switches f may be shifted withoutdisengaging the gearing which drives the feedwheel shaft 68 and withoutstopping the moving parts of the instrument.

The selecting switches f which are variably actuated by the tape, serveto variably connect the contacts 1, 2, 3, 4 and 5 of the transmitterdisk to a source of current to thereby determine the oharacter'of thecombinations of impulses imparted to the line as the transmitter switcharm a passes over these contacts. Preferably, a second set of fiveswitches 9 (see Fig. 11) are interposed between the switches f and thetransmitter disk and are operated bya set of magnets G. The switches fare all connected by a conductor 83 to one side of the local battery Hand the contacts of these switches are connected respectively by a setof conductors 84 to the coils of the magnets G, the coils of the magnetsbeing also connected to the ground or by a suitable return conductor tothe opposite side of the battery H. The set of switches g are connected,respectively, by a set ofconductors 85 to the contacts 1, 2, 3, 4 and 5of the transmitter disk.

The characters are represented by permutations of five impulses ofopposite polarity. For this reason, the switches 9 form pole changers,the contacts of which are connected by conductors 86 and 87 to theopposite sides of a divided battery H, the normally engaged or backcontacts being connected to the negative pole of the battery and thenormally disengaged or front eontacts to the positive pole thereof. Theconductors 86 and 87 also directly connect the contacts 6 and 7 of thetransmitter disk to the negative and positive poles, respectively, ofthe divided battery H. The gearing be tween the main shaft 11 and thefeed wheel for the tape is such that the tape advances through the spaceoccupied by a single transverse row of perforations during eachrevolution of the transmitter switch arm a. The switches f which arevariably operated by the perforations variably actuate the magnets Grand the pole changing switches g so that, as the transmitter switch armpasses over the contacts 1, 2, 3, 4 and 5, different permutations offive impulses of opposite polarity are imparted to a conductor 88 whichis connected to the brush 25 that engages the hub of the switch arm. Atthe end of each permutation, the switch arm it passes over the contacts6 and 7, so that, at the end of each permutation of lmpulses, a negativeimpulse followed by a positive 1mpulse is always imparted to the line.

. The conductor 88, instead of forming the line conductor, preferablyextends through a polarized pole changing relay P, the contacts 'ofwhich are connected by conductors 89 .to 'the opposite sides of adivided line battery J and the tongue p of the pole The line circuit isarranged for duplex operation, so that messages may be transmitted}simultaneously in both directions. For this purpose, the pole changingswitch 72 is 0011- nected by a conductor 90 to a pair of branchconductors 91 that lead, respectively, to the coils of a local main linerelay B. This relay is polarized, one coil being connected to a groundedartificial line 92 and the other to a line conductor 93 which extends,as shown in Fig. 11, to a distant station and to the main line relay Rthereof. Vith this arrangement, the main line relay at each stationwill, of course, only respond to current impulses imparted to the linecircuit from the other station.

The switch tongue 1- of the line relay at each station is connected to aconductor 94 which leads from the local battery H. Its contact isconnected by a conductor 95 to the brush 25 of the receiver switch arm6. A set of branch conductors 96 connect the contacts 1, 2, 3, 1 and 5of the receiver disk at each station to a set of five selecting relaysor magnets K. Extensions 96 of the conductors 96 are also connected tothe contacts of a set of normally closed switches Z which are operatedby a magnet L. These switches are connected by a set of conductors 97 toa set of five operating magnets M, and the contact 6' of the receiverdisk is connected by a conductor 98 to the coil of an unlocking magnet Nthatis associated with the set of selecting magnets or relays K. Anextension 98 of the conductor 98 is connected to the normally engagedcontact of a switch Z" which is also operated by the magnet L. Thisswitch is connected by a branch conductor 99 to the coil of the magnet Land to the coil of a magnet T which is associated with the set ofoperating magnets M. The unlocking magnet N operates a normally closedswitch at which is connected to the battery wire 83 and the contact ofwhich is connected b a conductor 100 to the contacts of a serles ofnormally open, locking switches is which are operated by the selectingrelays K and which are connected to the set of branch conductors 96.When any one of the selecting magnets K is energized, the correspondinglocking switch is shifted and connects its coil through the medium ofthe conductor 100 and switch n. to the local battery. In this way, anyof the selecting magnets which are operated remain energized and thebranch conductors 96 cont-rolled thereby remain connected to the localbattery until the unlocking switch It is opened.

The set of operating magnets M also control a series of normally openlocking switches m. The contacts of these switches are connected by aconductor 101 to the contact of a normally closed switch 25 of anunlocking magnet T. The circuit of this "by a suitable return conductorto the local ance with the polarity. of the succeeding imbattery H. v

The local battery circuit through the re volving switch arm I) of thereceiver disk is opened and closed by the tongue 1 of the local linerelay R in response to the positive and negative impulses transmittedfrom'the distant station. When a negative impulse from a distant stationpasses through the line relay, its switch tongue closes the localcircuit, and a positive impulse over the line circuit shifts the switchtongue and opens the local circuit. The receiver and transmitter switcharms a and b are operated in unison, so that they pass over the contacts1, 2, 3, 4 and 5 of the transmitter and {ireceiver disks in synchronism.As the switch arm b at either station passes over the contacts 1, 2, 3,4 and 5, of the receiver disk, the branch conductors 96 and selectingrelays 70 will be variably selected and energized in accordance with thevaried permutations of impulses transmitted over the line circuit fromthe other station and which represent selecting relay K at the otherstati'onwill be energized and the first branch conductor 96 and itsextension 96 will be selected and connected tothe local battery throughthe medium of the locking switch controlled by this magnet. .If thefirst impulse of the per mutation is positive, the relay K connected tothe contact 1 of the receiver disk will not be energized. In a similarmanner, the selecting relays K connected to the contacts 2, 3, 4 and 5are variably operated in accordpulses of the permutation.

In this way, as a. message is received at either station, one or moreofthe branch conductors 96 are selected and connected to the local batteryH during each revolution of the receiver switch arm I). At the sametime, if the magnet L is deenergized and the switches Z closed, one ormore of the set of conductors 97 are selected and one or 'more of. theoperating ma nets M are energized. When anyone 0 the magnets M isenergized, its locking switch is shifted to i the selected operatingmagnets remain energized independently of the selecting relays K untilthe unlocking switch t is ,opened,

The set of operating magnets M can be emcircuit through the receiverswitch arm I) and through the conductor 98 and the unlocking magnet N.Switch n is then shifted to open the local circuit through the set ofselecting relays K, so that the latter are then ready to receive thenext' signal. This unlocking switch, however, does not open the circuitsthrough the operating magnets M which have been selected, since thecoils of these magnets are connected by their locking switches to thelocal battery through the unlocking switch If. The impulse from contact6 of the receiver disk also passes by the conductor 98 and switch Z tothe coil of the magnet v This magnet is thus energized to shift theswitches Z and Z and thereby disconnect the circuits of the operatingrelays M from the circuitsof the se lecting relays K. Switch Z is alsoprovided with a normally open contact which is connected to the localbattery H by the conductor 101, so that, when the magnet is operated,the circuit through its coil is locked in closed condition and itremains energized until the normally closed unlocking switch t isopened. By thus separating the operating magnets M and the selecting.

relays K, the latter may be employed to build up one character, whilethe magnets M are operating to print or record the preceding character.The impulse from contact 6 of the receiver disk also closes the circuitthrough the conductor 98, its extension 98, switch Z", conductor 99 andthe relay T and the circuit through the coil of this relay is locked inclosed position by the shift of the switch Z. Relay T then closes itsnormally open switch t and the circuit is completed from the batterywire- 94 through switch If and conductor 102 through the coil of theunlocking magnet T.- It takes some appreciable interval of time toenergize magnet T and subsequently energize the unlocking-magnet T, sothat ample time is afforded for the. recording or printing-operationeffected by the set of magnets. M, but when this operation is completed,

magnet. T shifts the unlocking-switch t and opens the circuits throughthe operating magnets and also through the magnets L, T and T. Theswitches of these magnets thendrop back to normal position and the setof switches Z again connect the set of relays K to the set of conductors97 that conductors 96 that lead fromthe selecting lead to the operatingmagnets. The latter are then again actuated in accordance with thesignal which has been previously built up by the selective operation ofthe rela s lt should be noted that the selecting relays actuated duringa single revolution of the receiver switch arm are necessarily operatedone after another as the receiver switch 7) passes over its contacts 1,2, 3, 4 and 5, and each relay K must be capable of operating during theinterval that the switch is passing over a single contact. But the operatingmagnets M that are selected by any one slgnal or permutation ofimpulses are connected to battery practically simultaneously when thedivide magnet L is deenergized. The circuits of the operating magnets Mare, as stated, then locked into connection with the battery by means ofthe locking switches m controlled thereby and, as the receiver switch 1)passes over its contact 6', the divide magnet L is actuated to M withoutreducing the speed of operation --of the receiver switch and of .relaysK. The contact 6' the selecting of the receiver disk is preferablyelongated, as shown, so

that the operations of the restoring or unlocking magnet N and of thedivide magnet L are effected with certainty between separatesi nals.

In ig. 11, the circuits at two connected stations are diagrammaticallyindicated.

The instruments and circuits of both stations are alike, except thatcorrecting means is provided only at the station Y. At this correctingstation, the shaft 11 which operates the transmitter and receiverswitches a and b is connected to the operating motor through the mediumof correcting devices controlled by the magnet D, as previouslydescribed; The controlling switch E for this magnet is connected to theconductor 1 95 that relay switch 1' at this station. A conductor coil ofthe magnet Dto ground. At the ads from the contact of the line 103extends from the contact E through the other non-corrected station, theshaft 11 and switch arms a and b thereon are driven directly from themotor.

Toefi'ect the operation of the correcting magnet D at station Y, bothswitches E and 7' must be in closed position for a suflicient intervalof time to energize the coil of this magnet. Relayswitch 1' is of coursecontrolled by the rotating transmitter switch (L at the non-correctedstation X, while switch E is controlled by the cam c that rotates withthe shaft 11 and switch arms a and Z) at the corrected station Y. Themotor at station Y is preferably adjusted to run slightly faster thanthe motor at station X, so that the switches a and Z) and cam c at theformer station tend to advance relatively to the switches a and F) atthe latter station. As the receiver and transmitter switches pass overtheir contacts 1, 2, 3, 4 and 5, and cam 6 holds the switch E away fromthe contact E so that the circuit of the correcting magnet is open atthis point. As the transmitter switch at station X passes over itscontacts 6 and 7 it invariably imparts to the line a negative impulsefollowed by a positive impulse, so that the relay switch 7* at station Yis closed for a brief interval, as indicated in Fig. 11. But in theIposition of the cam 0 shown. the switch is still held open so that thecorrecting magnet is not operated. However, as shaft 11 and cam e atstation Y advance. relatively to the shaft 11 and transmitter switch aat station X, the recessed portion 6 willpermit the shift of the switchE to closed position, at the same time that the relay switch 1 at thisstation is held in closed position by the correcting impulse imparted tothe line by the transmitter switch a at station X. When both theswitches E and 1" that control the circuit of the correcting magnet Dare simultaneously closed for a sufiicient interval, the magnet isenergized and the pin 46 carried by its armature lever d is shifted andoperates to retard the movement of the shaft 11 and of the transmitterand receivin switches a. and b at the correcting station Y The negativeimpulses thus imparted to the line from the contact 6 of the transmitterdisk A at station-X are always of the same length, since they areinvariably followed by a positive impulse from the contact 7 of thetransmitter disk. This negative iu1- pulse thus not only acts as arestoring impulse for the receiver at station Y, but also acts as acorrecting impulse to maintain the instruments at both stations insynchronism. This impulse is always transmitted over the line when thetwo sets are in communication, even though no message is transmittedfrom station X. If desired, the motor at the corrected station could bedriven slower than the motor at the noncorrected station andrthe devicecontrolled by the correcting magnet D arranged to advancethe transmitterand receiver switches at the corrected station.

There is a certain amount of lag in the line circuit due to the intervalof time required to charge the line and operate the relays in the line.For this reason, the receiver disk B ateach station is rotatablyadjustable, as described, so that it may be placed in proper phase withthe transmitter at the other station. In effecting this ad justment, thereceiver disk is shifted by the handle 18 thereon and the limits ofadjustment between which the receiving apparatus will operate properlyare determined by reading the scale associated with the handle 18. Thereceiver disk is then turned until it occupies a position half waybetween the limits thus determined, so that the reversals of polarityimparted to the line by the transmitter at the distant station occurwhen the receiver switch is mid-way between the contacts of its disk.Preferably, as indicated in Fig. 11, the character selecting contacts 1,2, 3, 4 and 5 of the receiver disk are some what smaller than those ofthe transmitter disk, so that ample opportunity is afforded forreversals in the line circuit while the receiver switch is between itscontacts.

In the arrangement indicated in Fig. 11, the correcting impulses passover the line in one direction only from the non-corrected station X tothe corrected station Y. Variations in the line lag equally effect thetransmission of the correcting impulses and the transmission ofcharacter signals from station X to station Y, so that the receiver diskat station Y, when once set in proper position, need not be readjustedin case the line lag varies on account of varying weather conditions andthe like. But such variations will cause variations in phase between thecorrecting impulses imparted to the line from station X and thecharacter signals transmitted. in the opposite direction over the linefrom station Y, so that the receiver disk B at station X must bereadjusted from time to time. For this reason, means is preferablyprovided for rotating the re:- ceiver switches at both stations fasterthan the transmitter switches, and correcting de-' vices are employedfor retarding the re ceiver switch only. A station instrument of thissort is shown in Fig. 9. i The construction is substantially similar tothat previ ously described, except that the transmitter and receiverswitch arms a and bare mounted on separate horizontal shafts 11"-portions 12 of the disk supporting standards are both provided withU-shaped members 14 wherein the outer ends of. the shafts are journaled.The inner ends of the shafts are journaled in an upright'15', which alsocarries a stud 107 whereon the intermediate pinion 105 is mounted. Gear104 is fixed to the shaft 11*, but the gear 106 is secured to the loosesleeve or hub 36 of the gear 37 on the receiver shaft 11". Gear 106 isslightly smaller than the gear- 104 and preferably has one tooth less,so that it rotates at a slightly greater speed. As in the constructionpreviously described, the loose gear 37 is connected to its shaft bycorrecting earing which is controlled by the ma net The switch E andcame for control ing the circuit of the magnet D are associated with thereceiver shaft 11 and the feed mechanism for the tape is driven from thetransmitter shaft 11.

The circuits at the connected stations are similar in all respects tothose shown in Fig. 11, except that, as indicated in Fig. 12, eachstation is provided with a correcting magnet D, and a controlling switchE therefor. Vith this arrangement, the motors and the transmitterswitches of both station instruments are operated at substantially thesame speed, although they need not, and indeed cannot, be operated inexact synchronism. But it is essential thatthe speed of both motorsshall be so nearly uniform that the gears 106 at each station willrotate faster than the transmitter shaft at the other station, so thatthe receiver switch 5 at each station tends to advance relatively to thetransmitter switch a at the other station. As the transmitter switch aat each station passes over its contacts 6 and 7, the correctingimpulses will be imparted to the line which will close the line relayswitch '1' I at the other station, and the switches r and E at eachstation will cooperate to control the corresponding correcting magnet D,in the manner previously described, to retard the movement of eachreceiver switch I). In

this way, while the transmitter and receiver correcting impulses aretransmitted in one direction only from a non-corrected station X to acorrected stat on Y, as indicated in Fig. 11, the. proper transmissionof a message in the opposite direction is dependent upon the operationof the line relays R at both stations and of all repeating rela ys thatmaybe interposed in the line. This requires considerable nlcetyofadjustment in prop-' erly balancing the artificial linesconnected tothe line relays, particularly if there are a number. of repeating relaysemployed.

But, in the arrangement indicated in Fig.

12, each transmitter disk imparts both correcting impulses and characterselecting imfpulses or signals to the line and the trans instruments areused, it is frequently necessary to have both kinds at a single stationthat is connected with two or more other stations. With thisarrangement, each transmitter switch mechanism imparts impulses to theline and thereby controls the correcting devices of the rotary receiverswitch mechanism to which it is sending character signals, while its ownoperation is entirely under local control and is not affected byimpulses imparted to the lineor by the receiver correcting devices.- Itshould also be noted that the rotary receiver switch mechanisms, exceptas controlled at inter- .Vals by the correcting devices, are operativeunder local control to eflect character, selections, and that thecorrecting devices are operative independently of spacing interva'lsbetween the successive selecting impulses of each character signal.-

As indicated in Fig. 11, the contact 8 of each transmitter disk isconnected by a condu'ctor 108 to a switch key S, the contacts of whichare respectively connected to the opposite sides of a divided battery H.The

contact 8 of each receiver disk is connected to a conductor 109 thatextends through the coil of a lockin magnet W and through a signal lampW and this conductor is also connected to a normally open switch w thatis controlled by the magnet W. The contact of this switch is connectedto the local bat tery H by the conductor 100 and locking swltch n.Each'key S is normally connected to the positive pole of the localbattery, so

that positive impulses are imparted to the 'line as the transmitterswitch passes over its contact'S, and the switch tongue 1' of the linerelay 'R at the distant station is held in open position,'as thereceiver switch 6 at the'latt'er station passes over its contact 8.

But if, for example, the switch 8 at station X.is depressed, a negativeimpulse is trans-.

mitted that closes the relay switch 7* of the distant station Y as thereceiver switch I; of

this latter station passes over its contact 8. The circuit of the magnetW and signal I lamp W" at station Y is thus closed and is locked intoconnection with the local battery by switch w until the receiver switcharm 6 reaches its contact 6 and so energizes the unlocking relay N. Inthis way, the operator at either end of the line may signal the operatorat the other end, and so notify the latter in case a message is notproperly received.

Furthermore, these signal lamps may be employed in testing thesynchronism of the instruments at the opposite ends of the line byoperating both instruments without inserting any tape. Under suchcircumstances, the selecting switches f at both stations will be closedand positive impulses alone are imparted to the line by both transmitterswitches (1, except when the latter pass over the contacts 6 whennegative impulses will be transmitted. If the instruments are not insynchronism, one will advance relatively to the other, until thereceiver switch I) at one station passes over its contact 8 as thetransmitter switch a at the other station passes over its contact 6. Inthis way, the lamps at both stations will light at intervals when theinstruments are not in proper synchronism.

It is obvious that numerous changes may be made in the details set forthwithout departure from the essentials of the invention as defined in theclaims and" that certain features of the invention may be' employedwithout its adoption in entirety.

We-claim as our invention u 1. A station instrument for printingtelegraphs comprising rotating transmitter and receiver switches, acommon motor for continuously driving the same, correcting devicescontrolling said receiver switch, tape controlled means for selectingthe transmitted impulses, and feeding devices driven by said motor forcontinuously advancing the tape in definite timed relation to the speedof operation of said transmitter switch.

2. A station instrument for printing telegraphs comprisin transmitterand receiver disks, each provided with a circular series of contacts,rotating switch arms cooperating therewith, a common motor shaft fordriving said switch arms, correcting devices controlling the saidreceiver switch arm, a set/of tape controlled switches for selecting thetransmitted impulses, and gearing driven by said motor for continuouslyadvancing the ta e in timed relation with the rotation of saitransmitter switch arm.

3. A station instrument for printing telegraphs comprising rotatingtransmitter and receiver switch mechanisms, a common motor shaft fordriving the same, electrically controlled correcting devices for saidreceiver switch mechanism, a set of tape controlled switches forselecting the transmitted impulses, a pin-toothed feed wheel arranged toengage a longitudinal row of perforations in the tape, and speedreducing gearing conanism relatively to said motor shaft, a mag- 1 netfor actuating said correcting devices, a controlling switch forsaidmagnet, a cam rotating with said receiver switch mechanism foractuating said switch, tape. controlled means for selecting thetransmitted impulses,'and feed mechanism for the tape. geared to saidtransmitter switch mechanism.

5. In a printing telegraph in which the characters are represented bypermutations of adefinite number of impulses of opposite polarity, thecombination at each station, of rotating transmitter and receiverswitches, a common motor shaft for driving the same, correcting devicesfor shifting said receiver switch relatively to said drive shaft, acontroller for said correcting devices rotating with said receiverswitch,

tape controlled switch for selecting the transmitted impulses, and feedmechanism for advancing the tape geared to said transmitter switchmechanism.

6. In a printing telegraph in which the characters are represented bypermutations of a definite number of impulses of opposite polarity, thecombination at each station of a line relay, rotating transmitter andreceiver switch arms, contact disks cooperating with said switch arms, acommon motor shaft for driving said switch arms, correcting devices forshifting said receiver switch arm relatively to said motor drive shaft,an actuating magnet for said correcting devices, a cam rotating withsaid receiver switch arm, a switch actuated by said cam andcoiiperatingfwith said line relay to control said correcting magnet,tape controlled means. for selecting the transmitted impulses, and feedmechanism for said tape geared to said transmitter switch arm.

7 In a printing telegraph instrument, the combination of arotatingtransmitter switch mechanism, tape controlled means forselecting the imparted impulses, a toothed feed wheel arranged to engagea longitudinal row of perforations in the tape, and gearing connectingsaid feed wheel and said transmitter switch mechanism, said feed wheelbeing shiftable to release the tape.

8. In a printing telegraph instrument, the combination of a rotatingtransmitter switch mechanism,- tape controlled means for selecting theimparted impulses, a tape guide,

a toothedfeed wheel for the tape projecting into said guide,andconnecting gearing between said transmitter switch mechanism and saidfeed 'wheel, the latter being shiftable transversely out of the path ofthe tape during the operating of the instrument.

9. In a printing telegraph instrument, the

combination of a rotatingtransmitter. switch mechanlsm, a set of tapecontrolled switches for selecting the transmitted impulses, a tapeguide, a-toothed' feed wheel for the tape projecting into said guide,operating shafts for said transmitter switch mechanism andsaid feedwheel, and gearing con-.

necting said shafts, said feed wheel shaft being spring-held in normalposition to permit the shift of the feed wheel out of the path of thetape.

10. In a printing telegraph instrument, the combination of a rotatingtransmitter switch mechanism, a set of tape. controlled switches forselecting the transmitted impulses, a tape-guide, a toothed feed wheelfor-the tape projecting into said guide, a drive shaft for saidtransmitter switch mechanism, a support pivoted on said drive shaft, ashaft whereon said feed wheel is mounted journale'd in said support, andconnecting gears on said shafts, said support being path of the tape.

11. In a prlnting telegraph instrument,

the combination of a rotating transmitter switch mechanism,- a setoftape controlled switches for selecting the transmitted impulses, a tapeguide, a toothed feed wheel for the tape projecting into said guide,connecting. gearing between said transmitter switch mechanism and saidfeed wheel arranged to permit the shift of the latter out of the path ofthe ta e, and means controlled by the shift of sai path of the tape.

- 12. In a printing telegraph instrument, the combination of a rotatingtransmitter switch mechanism, a set of tape controlled switches forselecting the transmitted imulses, a tape guide, a toothed feed wheel orthe tape projecting into said guide, means for driving said feed wheel,and means for shifting said feedwheel and said selecting switches out ofthe path of the tape.

13. In a printing telegraph instrument, the combination of a rotatingtransmitter feed wheel for moving, said impulse selecting switches outof the switch'mechanism, a set of tape controlled switches for selectingthe transmitted impulses, a tape'guide, a toothed feed wheel for thetape projecting into said guide, a drive shaft for said transmitterswitch mechanism, a support pivoted on said shaft a shaft carrying saidfeed wheel journaled on said support, Worm gearing connecting saidshafts, an adjustable stop for positioning said support, a spring forholding said support against said support being shiftable away from saidstop for moving said feed wheel out of the path-of the tape and ashifterconnected to said support for simultaneously shifting said selectingswitches .out of the path of the tape.

14. In a printing telegraph instrument, the combination with a tapeguide, of a toothed feed wheel therefor, a set of tape controlledswitches. and means for shifting said feed wheel and switches out of thepath of the tape.

15. In a printing telegraph instrument, the combination with a tapeguide, of a toothed feed wheel therefor, a set of tape controlledswitches, a shiftable support whereon said feed wheel is mounted andconand adapted to be shifted thereby into and out of engagement withsaid contacts, and means for simultaneously shifting said switches awayfrom said contacts and out of the path of the tape.

1 17. A station instrument for printing telegraphs comprising rotatingtransmitter and receiver switch arms, cooperating contact disks. acommon motor shaft for driving said switch arms, and correcting devicesfor shifting said receiver switch arm relatively to said motor shaft,said receiver contact disks being rotatably adjustable, tape feedingmeans geared to said transmitter switch arm, and tape controlled meansfor selecting the transmitted impulses.

18. A station instrument'for printing telegraphs comprising separaterotating transmitter and receiver switch mechanisms for respectivelycontrolling sets of signal and character selecting circuits, a commonmotor shaft therefor, connecting gearing tending to drive said switchmechanisms at slightly difi'erent speeds, and correcting devicesindividual to the receiver switch mechanism for adjusting the samerelatively to said motor shaft.

19. A station instrument for printing telegraphs comprising rotatingtransmitter and receiver switch arms, cooperating contact diskstherefor, separate operating shafts for said arms. connecting gearingtending to rotate said shafts at slightly different speeds,

and correcting devices for adjusting said receiver drive shaftrelatively to said gearing.

20. A station instrument for printing telegraphs comprising rotatingtransmitter and receiver switch arms, cooperating contact diskstherefor, shafts whereon said arms are mounted, connecting gearingbetween said shafts, correcting devices for adjusting said receivershaft and switch arm relatively to said gearing, and an actuating motorconnected to said transmitter shaft.

21. A station instrument for printing telegraphs comprising rotatingtransmitter and receiver switch arms, cooperating contact diskstherefor, separate actuating shafts for saidswitch arms, connectinggearing tending to drive said switch arms at slightly different speeds,and correcting devices for said receiver switch arm, said receivercontact disk being rotatably adjustable.

. 22. In a printing telegraph, the combination of a duplexed linecircuit, separate, continuously rotating transmitter and receiver switchmechanisms at each station, and correcting devices brought intooperation under the joint control of the transmitter switch mechanism ateach station and the receiver switch mechanism at the other station formaintaining the same in synchronism.

23. In a printing telegraph in which the characters are of uniformlength and represented by permutations of a definite number of impulsesof opposite polarity, the combination of a duplexed line circuit, atransmitter at each station comprising a continuously rotating memberoperating solely under local control to impart the character signals andcorrecting impulses to the line, a receiver at each station operative toeffect the character selections in response to the received signals, andcontrolling devices individual to said receivers and responsive to thecorrecting impulses transmitted by the transmitter at each station tothe receiver at the other station for maintaining the same insynchronism. '24. In a printing telegraph, the combination of a duplexedline circuit, a line relay and an instrument at each station, eachinstrument comprising separate rotating transmitter and receiver switchmechanisms, and motor actuated means tending to drive the same atslightly different speeds, and means controlled by the combinedoperation of the line relay and the rotating receiver switch mechanismat each station for adjusting the latter relatively to the driving meansand maintain the same in synchronism with the transmitter switchmechanism at the other station.

25. In a printing telegraph instrument, the combination with a rotatingreceiver switch and a drive -shaft therefor. of correcting devicescomprising concentric members connected respectively to said shaft andsaid switch mechanism, a gear on one of said members, a cross armmountedon the other of said members and having a counter balance on oneend, a star wheel eccentrically mounted on the opposite end of said arm,two intermediate pinions mounted on said arm and connecting said'starWheel to said gear, a retaining device mounted on said arm andyieldingly engaging said star wheel, a correcting magnet, and a pinconnected to the armature ofsaid magnet andadapted to be shifted therebyinto and out of the path of movement of said star wheel.

,arranged to be moved thereby into and out of the path of movement ofsaid star wheel,

a controlling switch for said magnet, and a cam device rotating withsaid receiver switch mechanism for opening and closing said switch. 1

27. In a printing telegraph in which the characters are represented bypermutations of a definite number of impulses of opposite polarity, thecombination with a line circuit, continuously rotating transmitting andreceiving switchmechanisms at opposite ends of said line circuit, meansfor maintaining the same in synchronism, a set of tape controlled polechangers for selecting the permutation of impulses transmitted, and atoothed feed wheel arranged to engage a longitudinal row of perforationsin the tape,

, and continuously advance the same in definite timed relation to thespeed. of operation of said transmitter switch mechanism.

28. In a printing telegraph in which the characters are represented bypermutations of a definite number of impulses of opposite polarity, thecombination' of synchronously rotating transmitter and receiver switchmechanisms at the communicating stations, a set of pole changers adaptedto be controlled by the movement of a tape for selecting the transmittedsignals, means for continuously advancing the tape in definite timedrelation to the speed of operation of said transmitter switch mechanism,and a set of operating circuits selectively controlled by said receiverswitch mechanism.

29. In a printing telegraph, the combination of continuously rotatingtransmitter and as receiver switch mechanisms at the communicatingstations, means for maintaining the same in synchronism, a set ofswitches for controlling the transmitted impulses, a tape controllingsaid switches having a transverse series of perforations representingthe different signals and relatively inclined to the set of switchescontrolled thereby, said tape also having a longitudinal row ofperforations, and a toothed feed wheel geared to said transmitter switchmechanism and engaging the longitudinal row of perforations tocontinuously advance the same in definite timed relation to thespeed ofsaid synchronously rotating transmitter and receiver switch mechanisms.

30. In a printing telegraph, the combination of a duple'xed linecircuit, a line relay and an instrument comprising continuously rotatingtransmitter and receiver switch mechanisms at each station, means formaintaining the station instruments in synchonism, a set of switches ateach station adapted to be actuated by a moving tape to select thetransmitted impulses, feeding mechanisms for continuously advancing thetapes in definite timed relation to the speed of the rotating switchmechanisms,'and sets of recording circuits controlled by the receiverswitch mechanisms.

4 31. Ina printing telegraph, the combination of transmitter andreceiver switch mechanisms at communicating stations having rotarymotor-driven members, line-controlled correcting devices for adjustingsaid rotary receiver member, a set of selecting magnets operatively'associated in order with the line by said rotary receiver member andthereby controlled in combinations to eifect the selection of allcharacters of a message, locking circuits for said magnets, recordingmeans selectively controlled by said magnets, and additional magnetscontrolled by said rotary receiver member for controlling the recordingmeans and for opening said locking circuits in advance of the completerecording operation.

32. In a printing telegraph, a receiver switch mechanism comprising arotary member, line-controlled correcting device for adjusting saidmember, a series of local branch conductors and selecting circuitscontrolled by said switch mechanism, a set of operating circuits, and adividing switch mechanism controlled by said rotatingv receiver switchmember and arranged to alternately connect and disconnect said selectingand operating circuits. f

33. In a printing telegraph, a rotating receiver switch mechanism, aseries of local branch conductors, selecting circuits controlledthereby, a set of operating circuits, relays interposed in saidselecting circuits, operating magnets interposed in said operatingcircuits, a setof switches for connecting and disconnecting saidselecting and operating magnets, a divide magnet for operating said setof switches, locking switches controlled by said relays and magnets, anunlocking switch for said relays controlled by said receiver switchmechanism, and an unlocking switch for opening the circuits of saidmagnets when the operation thereof is completed.

34. In a printing telegraph, in which the signals are represented bypermutations of five impulses of opposite polarity-the combination ofrotating transmitter and receiver switch mechanisms at each station,means for maintaining the transmitter at each station in synchronismwith the receiver at the other station, each of said switch mechanismshaving contacts for character selecting and restoring impulses and anadditional contact for other signals, a pole changing switch keyconnected to the additional contact of each transmitter switchmechanism, a signal lamp and looking magnet connected to the additionalcontact of each receiver switch mechanism, a locking circuit for saidlamp controlled by said magnet, and means controlled by the restoringimpulse through the receiver switch mechanism for opening said lockingcircuit.

35. A station instrument for printing telegraphs comprising atransmitter and receiver switch mechanisms each having a rotating arm, acommon drive member for said rotating arms, correcting devices forchanging the position of the rotating arm of said receiver switchmechanism relative to said driving member, a set of tape-controlled polechangers connected to. the contacts of said transmitter switch mechanismand feeding devices for positively and continuously advancing the tapein timed relation with the rotation of said transmitter switch arm.

36. In a printing telegraph in which the characters are represented bypermutations of a definite number of impulses of opposite polarity, thecombination at each of two connected stations, of transmitter andreceiver switch mechanisms having separate rotating members, a commondrive shaft for said members, correcting devices under control of lineimpulses andoperative only on said receiyer switch member and adapted tochange the position thereof relatively to said drive shaft, a recordercontrolled by said receiver switch mechanism, and a setof pole changersconnected to the-contacts of said transmitting switch mechanism forselectin the permutations of impulses.

31in a printing telegraph in which the characters are represented bypermutations of a definite number of impulses of opposite polarity, thecombination at each of two connected stations, of transmitter andreceiver switch mechanisms having rotating members. a common drive shaftand connect ing gearing tending to drive said members at slightlydiiferent speeds, correcting devices individual to said receiver switchmember for changing the position thereof relatively to said drive shaft.means responsive to line impulses for controlling said correctingdevices, a recorder controlled by said receiver switch mechanism, a setof tape-controlled pole changers for selecting the transmitted impulsesand means for advancing the tape in timed relation with the operation ofsaid transmitter switch mechanism. a

38. In a printing telegraph in which the characters are representedbypermutations of a definite number of impulses of opposite polarity. thecombination of a normally closed duplexed line circuit. a rotatingtransmitter switch mechanism at each of two connected stations forimparting character signals and correcting impulses to the line. arotating receiver switch mechanism and a recorder controlled thereby ateach station, a common drive member for actuating the rotating membersof the transmitting and receiving switch mechanisms at each station atslightly ditlerent speeds and correcting devices at each station forchanging the position of the rotating member of the receiving switchmechanism relatively to said common drive member, said correctingdevices being under control of the correcting impulses imparted to theline by the transmitter switch mechanisms of the distant station.

39. In a printing telegraph, the combination with a normally closedduplex line circuit extending between two stations, a line relay and aninstrument at each station, each instrument comprising transmitter andreceiver switch mechanisms having rotating arms. sets of signal andcharacter selecting circuits controlled respectively by said switchmechanisms. a common actuating motor geared to said arms and tending todrive the same at slightly different speeds and correcting devices forchanging the position of said receiver switch arm relatively to saiddrive member, the correcting devices at each station having localoperating circuits under the joint control of the local receiver switchmechanism and correcting impulses imparted to the line by thetransmitted switch mechanism at the other station.

40. A station equipment for synchronous printing telegraph systems inwhich the character signals are of equal length and dis tinguished bypermutations of two diii'erent line conditions extendingthrough adefinite number of time intervals, said equipment comprising separaterotary transmitter and receiver members, sets of selectors correspondingto the signal intervals adapted to be operated in different combinationsand cooperating respectively with saidmembers to transmit the charactersignals and effect the character selections in response to receivedsignals, a common motor shaft and differential toothed gearing fordriving said rotary transmitter and receiver members at different speedsand for actuating said transmitter member solely under local control,and a line controlled correcting device individual to said rotaryreceiving member for adjusting the same at intervals relatively to saidmotor shaft.

41. In a synchronous printing telegraph system in which-the charactersignals are of equal length and distinguished by permutations of fivevaried impulses, the combination of a normally closed line, transmitterswitch mechanisms at connected stations each having a rotary memberoperative to impart the character signals and additional correctingimpulses to said line,'a' separate receiver mechanism at each stationcomprising a set of selectors operable in diiierent combinations and arotary member for associating said selectors in order with said line toeffect the character selections in response to received signals, motoractuated means operative to continuously rotate said transmitter memberssolely under local control and to actuate said rotary receiver membersunder local control during the character selecting operations atslightly greater speeds, and individual correcting devices under controlof the transmitted correcting impulses for retarding each of said rotaryreceiver members relatively to its driving means at intervals betweenthe character selections.

42. In a synchronous printing telegraph system, the combination of aline, separate transmitter and receiver mechanisms at each of twoconnected stations, each of said transmitter mechanisms comprising aseries of contacts, a'set of tape-controlled, signal selecting switchesconnected to said contacts and a rotary switch member cooperating withsaid contacts to impart to said line character signals of equal lengthand distinguished by permutations of a definite number of variedimpulses, each of said receiver mechanisms including a set of selectorsand a rotary member for associating said selectors in order with theline to efi'ect the character selections, means at each stationoperative solely under local control tocontinuously rotate saidtransmitter members and advance the tape in timed relation therewith andoperative to rotate said re ceiver member under local control during theselecting operations, and correcting devices under control oftransmitted line impulses and individual to each'of said rotaryreceiving members for adjusting the same relatively to its drivingmeans.

tape controlled, changers connected respectively to certain- 43. In asynchronous printing telegraph system inwhich the character signals areof equal length and distinguished by permutations of a definite numberof impulses'of opposite polarity,'the combination of a normally closedline, transmitter switch mechanism at connected stations each comprising a circular series of contacts, a set of signal selecting poleof saidcontacts, a rotary member cooperating with said selecting contacts andwith two additional contacts of said series to impart the charactersignals and additional controlling impulses to said line, and meansoperative solely under local control to .continuously rotate said switchmember and advance the tape in timed relation therewith, a receiver ateach station including a set of character selecting circuits, and aswitch mechanism operative under local control during the characterselections for associating said selecting circuits in order with theline, and means acting on the receiver switch mechanism at each stationand responsive to the controlling line impulses transmitted thereto tomaintain the same in synchronism with the transmitter switch mechanismat the other station.

445-. In a synchronous printing telegraph in which the character signals.are of equal length and distinguished by permutations of a definitenumber of varied impulses, the combination of a line transmitter andreceiver mechanisms ateach of two connected station's comprisingseparate rotary members, and sets of selecting devices cooperatingrespectively with the rotary transmitter and receiver members to impartthe signals to said line and effect the character selections in responseto received signals, driving means for continuously rotating saidtransmitter and receiver members at slightly different speeds and foroperating said transmitter members solely under local control, andindividual correcting devices for adjusting the rotary receiver membersat each station relatively to the driving means, each of said correctingdevices being under the joint control of the local receiver memher andthe distant transmitter member and brought into operation by the advanceof one of said members relatively to the other;

45. In a synchronous printing telegraph system in which the charactersignals are of uniform length and distinguished by permutations of adefinite number of impulses acter selecting circuits at each station andoperative respectively to impart the character signals to said line andeffect the character selections in response to received signals, each ofsaid switch mechanisms comprising relatively stationary and rotarymembers provided respectively with cooperating contacts, means at eachstation arranged to continuously operate said rotary switch members anddrive said rotary transmitter switch member solely under localcontrol,iand an individual correcting device for the rotary receiverswitch member at each station under the joint control thereof and of therotary transmitter switch memher at the other station and brought intoop eration by the advance of one of said n1embers relatively to theother.

. 46. In a synchronous printing telegraph system in which the charactersignals are of uniform length and distinguished by the permutation offive varied impulses. the combination of a duplexed line circuit.separate rotary transmitter and receiver switch mechanism and associatedmeans at each station operative respectively to impart the charactersignals to said line and efi'ect the character selections in response toreceived signals, motor-actuated means arranged to continuously operatesaid switch mechanisms and operate said transmitter switch mechanismssolely under local control, individual correcting devices for adjustingthe rotary receiver switch mechanism at each station relatively to itsdriving means, and an operating circuit for each of said correcting ldevices under the joint control of the local receiver switch mechanismand the distant transmitter switch mechanism and brought into operationby the advance of one. of said mechanisms relatively to the other.

47. In a printing telegraph, a rotating receiver switch mechanism,correcting devices therefor, means controlled by line impulses forsupplying currents to said switch mechanismanfl ffor controlling saidcorrecting devices,'a"series of local branch conductors operativelyassociated in order with said line-controlled means by said switchmechanism, selecting devices responsive to impulses through said'branchconductors. a set of operating circuits and magnets adapted to beenergized in combinations to effect the character selections, andswitching relay means controlled by said rotary switch mechanism forconnecting and disconnecting said selecting devices and said operatingcircuits.

48. In a printing telegraph, a receiver switch mechanism comprising arotary motor-driven member, correcting devices for adjusting saidmember, line controlled means for supplying current to said switchmechanism and for controlling said correcting meansa series of localbranch conductors operatively associated in order with theline-controlled means by said rotary switch member, a set of selectorsadapted to be set a series of local branch conductors connected incombination by impulses through said branch conductors to select allcharacters of a message, corresponding operating devices controlledrespectively by said selectors. an additional branch conductorcontrolled bv said rotary switch member and separate successivelyoperating magnets controlled thereby for restoring said selectors andoperating devices in the order named.

l9. In a printing telegraph. a receiver switch mechanism comprising arotary motor-driven member, correcting devices for adjusting said memberrelative to its driving means. line-controlled means for supplyingcurrent to said switch mechanism and for controlling said correctingdevices. a set of local branch conductors operatively associated inorder with said line-controlled means by said rotary switch memberduring the selection of each character of a message, a corresponding setof magnets responsive in combinations to impulses through saidconductors. relays interposed in at least some of said branchconductors, holding means for said relays. and means controlled by saidrotary switch member at each character selection for restoring saidrelays and effecting the delayed operation of the corresponding magnets.

50. In a printing telegraph, a receiver switch mechanism comprising arotary motor-driven member, correcting devices for adjusting saidmember. line-controlled means for supplying current to said switchmechanism and for controlling said correct i'ng devices, local branchconductors operatively associated in order by said switch member withsaid line-controlled means. a set of magnets responsive in combinationsto impulses through said conductors, impulse restoring devicesinterposed in at least some of said branch conductors and meanscontrolled by said rotary switch member at each character selection forrestoring all of said devices and effecting the delayed operation of thecorresponding magnets.

51. In a printing telegraph, the combination of a receiver switchmechanism comprising a rotary member, correcting devices therefor and aseries of cooperating contacts, means controlled by line impulses forsupplying current to said rotary member and for controlling saidcorrecting devices,

to said contacts, corresponding sets of selecting and operating circuitscontrolled bv said branch conductors in response to line impulses,locking and unlocking switch contacts for said circuits, dividing switchcontacts arranged to bring said selecting and operating circuitsalternately into and out of operative relation, and an additionalcontact and local branch conductor cooperating

